meli: implement flag set/unset action in UI

Also document it in manpages meli.1 and meli.7

Signed-off-by: Manos Pitsidianakis <manos@pitsidianak.is>

meli/docs/meli.1

@@ -265,6 +265,13 @@ Sqlite3 on the contrary at reasonable mailbox sizes should have a non noticable
 .It
 .Li flags = \&"flags:\&" flag | \&"tags:\&" flag | \&"is:\&" flag
 .El
+.Sh FLAGS
+.Nm
+supports the basic maildir flags: passed, replied, seen, trashed, draft and flagged.
+Flags can be searched with the `flags:` prefix in a search query, and can be modified by
+.Command flag set FLAG
+and
+.Command flag unset FLAG
 .Sh TAGS
 .Nm
 supports tagging in notmuch and IMAP/JMAP backends.

meli/docs/meli.7

@@ -445,6 +445,10 @@ which also has its complement
 .sp
 action.
 .Pp
+For e-mail backends that support flags you can use the following commands on entries and selections to modify them:
+.Command flag set FLAG
+.Command flag unset FLAG
+.Pp
 For e-mail backends that support tags
 .Po
 like

meli/src/mail/listing.rs

@@ -524,7 +524,7 @@ pub trait MailListingTrait: ListingTrait {
             };
             let account = &mut context.accounts[&account_hash];
             match a {
-                ListingAction::SetSeen => {
+                ListingAction::Flag(FlagAction::Set(Flag::SEEN)) | ListingAction::SetSeen => {
                     if let Err(err) = account.set_flags(
                         env_hashes,
                         mailbox_hash,
@@ -535,7 +535,7 @@ pub trait MailListingTrait: ListingTrait {
                         ));
                     }
                 }
-                ListingAction::SetUnseen => {
+                ListingAction::Flag(FlagAction::Unset(Flag::SEEN)) | ListingAction::SetUnseen => {
                     if let Err(err) = account.set_flags(
                         env_hashes,
                         mailbox_hash,
@@ -546,6 +546,28 @@ pub trait MailListingTrait: ListingTrait {
                         ));
                     }
                 }
+                ListingAction::Flag(FlagAction::Set(flag)) => {
+                    if let Err(err) = account.set_flags(
+                        env_hashes,
+                        mailbox_hash,
+                        smallvec::smallvec![FlagOp::Set(*flag)],
+                    ) {
+                        context.replies.push_back(UIEvent::StatusEvent(
+                            StatusEvent::DisplayMessage(err.to_string()),
+                        ));
+                    }
+                }
+                ListingAction::Flag(FlagAction::Unset(flag)) => {
+                    if let Err(err) = account.set_flags(
+                        env_hashes,
+                        mailbox_hash,
+                        smallvec::smallvec![FlagOp::UnSet(*flag)],
+                    ) {
+                        context.replies.push_back(UIEvent::StatusEvent(
+                            StatusEvent::DisplayMessage(err.to_string()),
+                        ));
+                    }
+                }
                 ListingAction::Tag(TagAction::Add(ref tag_str)) => {
                     if let Err(err) = account.set_flags(
                         env_hashes,
@@ -1635,6 +1657,7 @@ impl Component for Listing {
                         | Action::Listing(a @ ListingAction::CopyToOtherAccount(_, _))
                         | Action::Listing(a @ ListingAction::MoveToOtherAccount(_, _))
                         | Action::Listing(a @ ListingAction::ExportMbox(_, _))
+                        | Action::Listing(a @ ListingAction::Flag(_))
                         | Action::Listing(a @ ListingAction::Tag(_)) => {
                             let focused = self.component.get_focused_items(context);
                             self.component.perform_action(context, focused, a);

meli/src/mail/listing/compact.rs

@@ -941,6 +941,7 @@ impl CompactListing {
     ) -> EntryStrings {
         let thread = threads.thread_ref(hash);
         let mut tags_string = String::new();
+        let flags = root_envelope.flags();
         let mut colors: SmallVec<[_; 8]> = SmallVec::new();
         let account = &context.accounts[&self.cursor_pos.0];
         if account.backend_capabilities.supports_tags {
@@ -1004,7 +1005,26 @@ impl CompactListing {
                 SubjectString(subject)
             },
             flag: FlagString(format!(
-                "{selected}{snoozed}{unseen}{attachments}{whitespace}",
+                "{flag_passed}{flag_replied}{flag_seen}{flag_trashed}{flag_draft}{flag_flagged} \
+                 {selected}{snoozed}{unseen}{attachments}{whitespace}",
+                flag_passed = Some("P")
+                    .filter(|_| flags.contains(Flag::PASSED))
+                    .unwrap_or_default(),
+                flag_replied = Some("R")
+                    .filter(|_| flags.contains(Flag::REPLIED))
+                    .unwrap_or_default(),
+                flag_seen = Some("S")
+                    .filter(|_| flags.contains(Flag::SEEN))
+                    .unwrap_or_default(),
+                flag_trashed = Some("T")
+                    .filter(|_| flags.contains(Flag::TRASHED))
+                    .unwrap_or_default(),
+                flag_draft = Some("D")
+                    .filter(|_| flags.contains(Flag::DRAFT))
+                    .unwrap_or_default(),
+                flag_flagged = Some("F")
+                    .filter(|_| flags.contains(Flag::FLAGGED))
+                    .unwrap_or_default(),
                 selected = if self
                     .rows
                     .selection